Black plate (88,1)GMC Sierra Owner Manual - 2011
9-88 Driving and Operating
E85 has less energy per liter
(gallon) than gasoline, so you will
need to refill the fuel tank more
often when using E85 than when
you are using gasoline. SeeFilling
the Tank on page 9‑88.
Notice: Some additives are not
compatible with E85 fuel and can
harm the vehicle's fuel system.
Do not add anything to E85.
Damage caused by additives
would not be covered by the
vehicle warranty.
Notice: This vehicle was not
designed for fuel that contains
methanol. Do not use fuel
containing methanol. It can
corrode metal parts in the fuel
system and also damage plastic
and rubber parts. That damage
would not be covered under the
vehicle warranty.Filling the Tank
If the vehicle has a diesel engine,
see the Duramax diesel supplement
for more information.
{WARNING
Fuel vapor burns violently and a
fuel fire can cause bad injuries.
To help avoid injuries to you and
others, read and follow all the
instructions on the fuel pump
island. Turn off the engine when
refueling. Do not smoke near fuel
or when refueling the vehicle.
Do not use cellular phones. Keep
sparks, flames, and smoking
materials away from fuel. Do not
leave the fuel pump unattended
when refueling the vehicle. This is
against the law in some places.
Do not re-enter the vehicle while
pumping fuel. Keep children away
from the fuel pump; never let
children pump fuel.
The tethered fuel cap is located
behind a hinged fuel door on the
driver side of the vehicle. Vehicles
that have a FlexFuel badge and
a yellow fuel cap can use either
unleaded gasoline or ethanol fuel
containing up to 85% ethanol (E85).
See Fuel E85 (85% Ethanol) on
page 9‑87.
To remove the fuel cap, turn it
slowly counterclockwise.
Black plate (89,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-89
{WARNING
Fuel can spray out on you if you
open the fuel cap too quickly.
If you spill fuel and then
something ignites it, you could be
badly burned. This spray can
happen if the tank is nearly full,
and is more likely in hot weather.
Open the fuel cap slowly and wait
for any hiss noise to stop. Then
unscrew the cap all the way.
If the vehicle is a dual fuel tank
chassis cab model, and it runs out
of fuel, refuel the front fuel tank first
to ensure a quick restart.
Be careful not to spill fuel. Do not
top off or overfill the tank and wait a
few seconds after you have finished pumping before removing the
nozzle. Clean fuel from painted
surfaces as soon as possible.
See
Exterior Care on page 10‑108.
When replacing the fuel cap, turn it
clockwise until it clicks. It will require
more effort to turn the fuel cap on
the last turn as you tighten it. Make
sure the cap is fully installed. The
diagnostic system can determine if
the fuel cap has been left off or
improperly installed. This would
allow fuel to evaporate into the
atmosphere. See Malfunction
Indicator Lamp on page 5‑25.
The TIGHTEN GAS CAP message
displays on the Driver Information
Center (DIC) if the fuel cap is not
properly installed. See Fuel System
Messages on page 5‑46 for more
information.
{WARNING
If a fire starts while you are
refueling, do not remove the
nozzle. Shut off the flow of fuel
by shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
Notice: If a new fuel cap is
needed, be sure to get the right
type of cap from your dealer.
The wrong type of fuel cap might
not fit properly, might cause the
malfunction indicator lamp to
light, and could damage the
fuel tank and emissions system.
See Malfunction Indicator Lamp
on page 5‑25.
Black plate (90,1)GMC Sierra Owner Manual - 2011
9-90 Driving and Operating
Filling a Portable Fuel
Container
{WARNING
Never fill a portable fuel container
while it is in the vehicle. Static
electricity discharge from the
container can ignite the fuel
vapor. You can be badly burned
and the vehicle damaged if this
occurs. To help avoid injury to
you and others:
.Dispense fuel only into
approved containers.
.Do not fill a container while
it is inside a vehicle, in a
vehicle's trunk, pickup bed,
or on any surface other than
the ground.(Continued)
WARNING (Continued)
.Bring the fill nozzle in contact
with the inside of the fill
opening before operating
the nozzle. Contact should
be maintained until the filling
is complete.
.Do not smoke while
pumping fuel.
.Do not use a cellular phone
while pumping fuel.
Towing
General Towing
Information
Only use towing equipment that
has been designed for the vehicle.
Contact your dealer or trailering
dealer for assistance with preparing
the vehicle for towing a trailer.
See the following trailer towing
information in this section:
.For information on driving
while towing a trailer, see
“Driving Characteristics and
Towing Tips.”
.For maximum vehicle and trailer
weights, see“Trailer Towing.”
.For information on equipment
to tow a trailer, see “Towing
Equipment.”
Black plate (92,1)GMC Sierra Owner Manual - 2011
9-92 Driving and Operating
Driving with a Trailer
{WARNING
When towing a trailer, exhaust
gases may collect at the rear
of the vehicle and enter if the
liftgate, trunk/hatch, or rear-most
window is open.
Engine exhaust contains Carbon
Monoxide (CO) which cannot be
seen or smelled. It can cause
unconsciousness and even death.
To maximize safety when towing
a trailer:
.Have the exhaust system
inspected for leaks and make
necessary repairs before
starting a trip.
.Never drive with the liftgate,
trunk/hatch, or rear-most
window open.(Continued)
WARNING (Continued)
.Fully open the air outlets
on or under the instrument
panel.
.Adjust the Climate Control
system to a setting that
brings in only outside air
and set the fan speed to the
highest setting. See Climate
Control System in the Index.
For more information about
Carbon Monoxide, see Engine
Exhaust on page 9‑44.
Towing a trailer requires a
certain amount of experience.
The combination you are driving is
longer and not as responsive as the
vehicle itself. Get acquainted with
the handling and braking of the rig
before setting out for the open road. Before starting, check all trailer
hitch parts and attachments, safety
chains, electrical connectors,
lamps, tires, and mirrors. If the
trailer has electric brakes, start the
combination moving and then apply
the trailer brake controller by hand
to be sure the brakes work.
During the trip, check occasionally
to be sure that the load is secure
and the lamps and any trailer
brakes still work.
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving the vehicle without a trailer.
This can help to avoid heavy
braking and sudden turns.
Black plate (94,1)GMC Sierra Owner Manual - 2011
9-94 Driving and Operating
To avoid this, let the engine
run while parked, preferably on
level ground, with the automatic
transmission in P (Park) for a few
minutes before turning the engine
off. If the overheat warning comes
on, seeEngine Overheating on
page 10‑25.
Parking on Hills
{WARNING
Parking the vehicle on a hill
with the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface. If parking the rig on a hill:
1. Press the brake pedal, but
do not shift into P (Park) yet.
Turn the wheels into the curb if
facing downhill or into traffic if
facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the regular brakes
until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking brake and shift
into P (Park).
5. If the vehicle is four-wheel-drive, be sure the transfer case is in a
drive gear and not in N (Neutral).
6. Release the brake pedal.
{WARNING
It can be dangerous to get out of
the vehicle if the shift lever is not
fully in P (Park) with the parking
brake firmly set. The vehicle
can roll.
If the engine has been left
running, the vehicle can move
suddenly. You or others could be
injured. To be sure the vehicle will
not move, even when on fairly
level ground, use the steps that
follow.
Always put the shift lever fully in
P (Park) with the parking brake
firmly set.
If the transfer case on a
four-wheel-drive vehicle is in
N (Neutral), the vehicle will be
free to roll, even if the shift lever
is in P (Park). Be sure the transfer
case is in a drive gear —not in
N (Neutral).
Black plate (95,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-95
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
2. Start the engine.
3. Shift into a gear.
4. Release the parking brake.
5. Let up on the brake pedal.
6. Drive slowly until the trailer isclear of the chocks.
7. Stop and have someone pick up
and store the chocks.
Maintenance when Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See this
manual's Maintenance Schedule
or Index for more information.
Things that are especially important
in trailer operation are automatic
transmission fluid, engine oil, axle
lubricant, belts, cooling system,
and brake system. It is a good
idea to inspect these before
and during the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Trailer Towing
If the vehicle has a diesel engine,
see the Duramax diesel supplement
for more information.
If the vehicle is a hybrid, see
the hybrid supplement for more
information.
Do not tow a trailer during break‐in.
See New Vehicle Break-In on
page 9‑34 for more information.
{WARNING
The driver can lose control when
pulling a trailer if the correct
equipment is not used or the
vehicle is not driven properly.
For example, if the trailer is too
heavy, the brakes may not work
well or even at all. The driver and
passengers could be seriously
injured. The vehicle may also be
damaged; the resulting repairs
would not be covered by the
(Continued)
WARNING (Continued)
vehicle warranty. Pull a trailer
only if all the steps in this section
have been followed. Ask your
dealer for advice and information
about towing a trailer with the
vehicle.
Notice: Pulling a trailer
improperly can damage the
vehicle and result in costly
repairs not covered by the
vehicle warranty. To pull a trailer
correctly, follow the advice in
this section and see your dealer
for important information about
towing a trailer with the vehicle.
To identify the trailering capacity of
the vehicle, read the information in
“Weight of the Trailer” later in this
section.
Black plate (118,1)GMC Sierra Owner Manual - 2011
9-118 Driving and Operating
Integrated Trailer Brake
Control System
The vehicle may have an Integrated
Trailer Brake Control (ITBC) system
for electric trailer brakes.
This symbol is located on the
Trailer Brake Control Panel on
vehicles with an Integrated Trailer
Brake Control system. The power
output to the trailer brakes is based
on the amount of brake pressure
being applied by the vehicle’s brake
system. This available power output
to the trailer brakes can be adjusted
to a wide range of trailering
situations.
The ITBC system is integrated
with the vehicle’s brake, antilock
brake, and StabiliTrak (if equipped)
systems. In trailering conditions thatcause the vehicle’s antilock brake
or StabiliTrak systems to activate,
power sent to the trailer's brakes
will be automatically adjusted to
minimize trailer wheel lock-up.
This does not imply that the trailer
has StabiliTrak.
2500 and 3500 series vehicles
with StabiliTrak have a Trailer Sway
Control (TSC) feature. See
Trailer
Sway Control (TSC) on page 9‑124.
2500 and 3500 series vehicles
with StabiliTrak have a Hill Start
Assist (HSA) feature. See Hill Start
Assist (HSA) on page 9‑70.
If the vehicle’s brake, antilock
brake, or StabiliTrak systems are
not functioning properly, the ITBC
system may not be fully functional
or may not function at all. Make
sure all of these systems are
fully operational to ensure full
functionality of the ITBC system.
The ITBC system is powered
through the vehicle's electrical
system. Turning the ignition off
will also turn off the ITBC system. The ITBC system is fully functional
only when the ignition is in ON or
in RUN.
The ITBC system can only be used
with trailers with electric brakes.
{WARNING
Connecting a trailer that is not
compatible with the ITBC system
may result in reduced or complete
loss of trailer braking. There
may be an increase in stopping
distance or trailer instability which
could result in personal injury or
damage to the vehicle, trailer,
or other property. An aftermarket
controller may be available for
use with trailers with surge, air,
or electric‐over‐hydraulic trailer
brake systems. To determine the
type of brakes on the trailer and
the availability of controllers,
check with your trailer
manufacturer or dealer.
Black plate (120,1)GMC Sierra Owner Manual - 2011
9-120 Driving and Operating
The Trailer Brake Display Page can
be displayed by performing any of
the following actions:
.Scrolling through the DIC menu
pages using the odometer
trip stem or the DIC Vehicle
Information button (if equipped).
.Pressing a Trailer Gain
button—If the Trailer Brake
Display Page is not currently
displayed, pressing a Trailer
Gain button will first recall the
current Trailer Gain setting.
After the Trailer Brake Display
Page is displayed, each press
and release of the gain buttons
will then cause the Trailer Gain
setting to change.
.Activating the Manual Trailer
Brake Apply lever.
.Connecting a trailer equipped
with electric trailer brakes.All DIC warning and service
messages must first be
acknowledged by the driver
by pressing the odometer trip stem
or the DIC Vehicle Information
button (if equipped) before the
Trailer Brake Display Page can
be displayed and Trailer Gain
can be adjusted.
TRAILER GAIN: This setting is
displayed any time the Trailer Brake
Display Page is active. This setting
can be adjusted from 0.0 to 10.0
with either a trailer connected or
disconnected. To adjust the Trailer
Gain, press one of the Trailer Gain
adjustment buttons located on the
Trailer Brake Control Panel. Press
and hold a gain button to cause the
Trailer Gain to continuously adjust.
To turn the output to the trailer off,
adjust the Trailer Gain setting to
0.0 (zero).
0.0 (zero) gain is the factory default
setting. To properly adjust trailer
gain, see
“Trailer Gain Adjustment
Procedure” later in this section.
TRAILER OUTPUT: This is
displayed any time a trailer with
electric brakes is connected.
Output to the electric brakes is
based on the amount of vehicle
braking present and relative to
the Trailer Gain setting. Output
is displayed from 0 to 10 bars for
each gain setting.
On vehicles with Trailer Sway
Control (TSC) or Hill Start Assist
(HSA), output to the electric trailer
brakes may be displayed when the
systems are active. See Trailer
Sway Control (TSC) on page 9‑124
and Hill Start Assist (HSA) on
page 9‑70.